A board foot is actually a measure of volume of lumber in the United States and Canada.
A single board foot is equivalent to 1 square foot of lumber that is 1 inch thick, meaning it has a length of 12 inches, a width of 12 inches, and a thickness of 1 inch
Formula to calculate board feet.
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Example:
Suppose you have a 4 inches thick board, if its width is 3 inches, calculate the board footage if its length 2 feet.
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Therefore, the board footage is 2.